Electrical cable support for mines



Feb, M, 1958 E. C. WHITFIELD ELECTRICAL CABLE SUPPORT FOR MINES Filed June 50, 1955 INVENR (Vi/j ATTORNEY United States Patent ELECTRICAL CABLE SUPPORT FOR MINES Edward c. Whitfield, Kitts, Ky.

Application June 30, 1955, Serial No. 519,177

4 Claims. (Cl. 248-49) The present invention relates in generalto cable supports, and more particularly to overhead bridge units for supporting electrical cables, flexible tubing and the like across passageways of mines.

In the present-day operation of coal and other underground mines, many varieties of electrical machinery are employed in addition to the usual electrical locomotives for pulling the ore cars. For example, many mines now employ electrically driven cutting machines and loading machines for cutting the coal or ore from the veins or blast piles and for loading the cut coal or ore onto the ore cars. Such machinery, of course, is located at the far or remote ends of the rooms of the mine, so that a large number of insulated electrical supply cables must be trained from the mine entrance to the remote locations of the electrical machinery. In addition, flexible tubing for supplying various machinery required in such remote locations in a mine must be trained from the mine entrance as the source of the medium supplied through the tubing frequently cannot be taken into the confined space in the mine. Since the machinery supplied by the electrical cables or tubing must be moved to different locations as the mining operation progresses, the cables or tubing cannot be permanently laid from the entrance to the location of the mining machinery.

It is obvious that such cables or tubing cannot be merely trained along the mine floor to the machinery location and allowed to lie in exposed condition, if the mine employs mining railroad equipment for transportation of the coal or ore, as the cable or tubing must cross the tracks at many points in the usual mine to reach the machinery locations, and would be subject to cutting or short circuiting by the wheels of the railroad rolling stock or a source of possible derailment of the rolling stock. In such cases, it has been the common practice to stretch the cable or tubing over the tracks between the timbers supporting the mine roof. However, this involves a substantial labor expense as the cables must be frequently moved and the cabels are subject to sagging between the timbers since they are unsupported over this region, and therefore are likely to be torn down by moving trafiic.

An object of the present invention, therefore, is the provision of a novel adjustable bridge unit providing overhead support for cables, tubing and the like in mines at points where the cable or tubing must cross over the tracks of a mine railroad system.

Another object of the present invention is the provision of a novel mine cable supporting bridge having means providing non-sagging support for the cable along the roof line of mine tunnels at points where the cable must cross tracks of a mine railroad system.

Another object of the present invention is the provision of a novel mine cable supporting bridge providing overhead support for cables at points where the cable must cross over mine haulways, which bridge is adjustable to accommodate to various inclinations of roof lines.

2,823,001 Patented Feb. 11, 1958 Another object of the present invention is the provision of a novel mine cable supporting bridge providing overhead support for cables, wherein the bridge is capable of accommodating heaving of the mine floor without damage to the bridge.

Other objects, advantages and capabilities of the present invention will become apparent from the following detail description, taken in conjunction with the accompanying drawing showing only a preferred embodiment of the invention.

In the drawing:

Figure 1 is a perspective viewof a mine cable supporting bridge embodying the present invention;

Figure 2 is a side elevation of one leg and a frag mentary portion of the cross-bar of the bridge;

Figure 3 is a vertical section view of the end portion of one of the legs of the bridge, taken along the line 3-3 of Figure l; s

Figure 4 is a section view taken from the same section plane of Figure 3, illustrating a yieldable fitting associated with the bridge leg for avoiding bending of the legs when heaving or swelling of the mine floor occurs.

"Referring to the drawin wherein like reference characters designate corresponding parts throughout the several figures, the mine cable supporting bridge, generally indicated by the reference character 10, is formed with a cross-bar. 11 corresponding in length approximately to the Width of the average haulway or mine tunnel, the cross-bar 11 being formed in the preferred embodiment of tubular pipe which is externally threaded at opposite ends. The cross-bar 11 is pivotally interconnected to depending legs 12 and 13 by means of hinges 14 to permit the axis of the cross-bar 11 to be shifted at will to various inclinations from the horizontal in order to accommodate the cross-bar 11 to irregular or inclined tunnel roofing.

The hinge joints 14 are each formed from a lower pair of laterally spaced hinge knuckles 15 which are welded to and extend upwardly from the upper end of tubular pipe sections 16 of uniform length constituting the upper portions of each leg 12 and 13. The hinge knuckles 15 are interconnected by means of a hinge pintle 17 with a laterally spaced pair of hinge knuckles 18 adapted to overlie the oppositely disposed surfaces of the hinge knuckles 15, which knuckles 18 are welded or otherwise rigidly secured to internally threaded end fit tings 19 threaded to the opposite ends of the crossbar 11.

The lower portions of the legs 12 and 13 are formed by threaded bars 20 terminating at their lower ends in pointed bearing members 21 fixed to the threaded shaft portions of the thread bars 20 to be forced into the floor of the mine tunnel or haulway and prevent transverse displacement of the legs 12 and 13. The upper threaded shaft portions of the thread bars 20 are threaded into internally threaded fittings 22 fixed onto the lower ends of the tubular pipe sections 16 of the legs 12 and 13 lower end of the tubular pipe section 16 of each leg and.

permit adjustment of the height of the leg. The crossbar 11 and the tubular pipe sections 16 of the legs 12 and 13 are each provided substantially along the entire length thereof with laterally projecting peg-like fingers 26 of small diameter which lie in the planes aligned withthe longitudinal axes of the cross-bar 11 and leg portions 16. These laterally projecting fingers 2 6 which extend In the use of the present invention a bridge'10 is dis-.-

posed transversely of the mine railroad system, track at the points where the electrical supply cables andtthe' flexible tubing are required to cross over the'track to' reach the mining machinery at the remote locations in the mine by positioning the legs 12 and 13 on opposite sides of the track at the cross-over point to dispose the legs 12 and 13 on parallel vertical axes with the pointed bearing members 21 in engagement with the mine floor. The handles 23 are then rotated outwardly to dispose them as far away from the leg thread bars 20 as possible and the handles are rotated in a proper direction to progressively project the thread bars 20 from the pipe portions 16 of the legs 12 and 13, until the terminal fittings 19 of the cross-bar 11 are jammed against the roof of the mine. When this operation is completed on each leg 12 and 13, the cross-bar 11 will then assume a position corresponding to the inclination of the roof. The cable to be laid across the track may either be woven along the legs 12 and 13 and the cross-bar 11 alternating above and below the laterally projecting fingers 26 prior to erection of the bridgeor after the bridge has been placed in position and adjusted to frictionally jam the same between the mine roof and mine floor. The pointed ends of the bearing members 21 of the legs will, of course, be driven into the floor by the torque produced upon rotation of the handles 23 so as to prevent accidental shifting of the legs and collapsing of the bridge unit. This construction, of course, provides an easy facility for training the necessary supply cables or'tubing from the entrance of the mine to the'points of use of the operating mining machinery by maintaining the cables in the region of the tunnel roofs at the necessary cross-over points along the railroad track system to prevent the cables sagging to a position where they might obstruct mine trafiic.

As illustrated in Figure 4, a yieldable leg fitting 30 may also be associated with the pointed bearing members 21 of the legs 12 and 13 to provide a yieldable section in each of the legs so as to permit the legs to longitudinally accommodate slight variations in length resulting from yielding or shifting of the mine floor as the mine floor swells or heaves from weight. These fittings 30 are provided with an upwardly opening well 31 complementary to and designed to precisely accommodate the smaller diameter downwardly projecting portions of the pointed bearing members 21, and a connecting eccentric bore 32 extending from the lower end of the fitting sleeve 30 to a point approximately mid-way between the ends thereof, which is designed to accommodate a coil spring 33 in such a manner that a limited arcuate portion of the upper turn of the coil spring 33 is exposed to be contacted by the downwardly projecting end of the pointed bearing members 21 of the legs 12 and 13. The coil spring 33 provides a yieldable support for the lower ends of the legs 12 and 13 so as to permit limited longitudinal compression of the legs. The tension on the coil spring 33 is adjusted by means of a downwardly pointed bearing screw 34 threaded into the lower end of the fitting sleeve- 30 and having diametrically opposite flats 35 thereon to facilitate rotation of the bearing screw 34 and adjustment of the coil spring tension by means of a wrench or like tool.

While but one particular embodiment of the invention has been particularly shown and described, it is apparent that other various modifications may be made in the invention without departing from the spirit and scope thereof, and it is desired, therefore, that only such limitations shall be placed thereon as are imposed by the prior art and are set forth in the appended claims.

v I claim: V V,

1 A bridge for supporting electrical supply cables and the like in an unobstructing position across trafficpaths in mine tunnels comprising an elongated tubular cross-bar, a supporting leg composed of telescopic sections for each end of the cross-bar, pointed bearing members fixed on the lower ends of each of the lowermost telescopic sections of said supporting legs to be driven into the mine floor to restrain lateral shifting of the lower ends of said legs, hinge joints interconnecting the upper ends'of the uppermost telescopic sections of said legs with the ends of said cross-bar, means for elongating and contracting said legstto jam the ends of said cross-bar .against the mine roof and align the cross-bar with the slope of the mine roof, and a plurality of laterally oppositely projecting fingers extending from said cross-bar in the longitudinal transverse plane thereof throughout its length and extending from the major portions of said 7 legs in the longitudinal transverse planes thereof providing parallel supports extending transversely oftthe dire'c-t tion of said cables about which said cables may be woven to r'est'rainthe cables within the planes of said cross-bar andrlegs. t

2. A bridge for supporting electrical supply cables and the'likeinan unobstructing position across traflic paths in mine tunnels comprising an elongated tubular cross-bar, a supporting leg composed of telescopic sections for each end of the cross-bar, said legs having upper tubular sections of equal length and lower threaded bars threaded into the lower ends of said tubular sections, pointed bearing members fixed on the lower ends of each of said threaded bars to be driven into the mine floor to restrain lateral shifting of the lower ends of said legs, hinge joints interconnecting the upper ends of said uppermost tubular sections of said legs with the ends of said cross-bar, means for rotating said threaded bars relative to their associated tubular sections to vertically adjust the length of'said legs to jam the ends of said cross-bar against the mine roof and align the cross-bar with the slope of the mine roof, and a plurality of laterally oppositely projecting fingers extending from said cross-bar in the longitudinal transverse plane thereof throughout its length and extending fromsaid tubular sections of said legs in the longitudinal transverse planes thereof providing parallel' supports extending transversely of the direction of said cables about which said cables may be Woven to restrainthe cables within the projected transverse planes of said cross-bar and legs.

' 3'. A bridge for supporting electrical supply cables and r the like inan unobstructing position across traffic paths sections of said legs with the endsof said cross-bar, handle means piyotallymounted on each of said threaded bars to be'selectively folded alongside or' projected outwardly 7 from its-associated threaded'bar, means for rotating said threaded bars relative to their ass'ociatedtubular sections to vertically adjust the length of said-legs to'jam the ends ofsaidcross-baragainst the mine roof and align the crossbar withthe slope of the mine roof, and a plurality of laterally oppositely projecting peg-like fingers extending fromsaid; cross-bar in the longitudinal transverse plane thereof throughout its length and extending from said tubular sections of said'legs' in the longitudinal transverse planes thereof providing parallel supports extending trans cross-bar and legs.

4. A bridge for supporting electrical supply cables and.

the like in an unobstructing position across traffic paths in mine tunnels comprising an elongated tubular crossbar, a supporting leg composed of telescopic sections for each end of the cross-bar, said legs having upper tubular sections of equal length and lower threaded bars threaded into the lower ends of said tubular sections, pointed bearing members fixed on the lower ends of each of said threaded bars, hinge joints interconnecting the upper ends of said uppermost tubular sections of said legs with the ends of said cross-bar, means for rotating said threaded bars relative to their associated tubular sections to vertically adjust the length of said legs to jam the ends of said cross-bar against the mine roof and align the crossbar with the slope of the mine roof, yieldable sleeve members associated with each of said bearing members having a socket complementary to the pointed portions of said bearing members in which said pointed portions are seated and a connecting eccentrically related bore, a coil spring disposed in said connecting bore, said spring being positioned by said connecting bore to dispose a portion of the uppermost turn thereof within said well in contact with the bearing member seated therein, downwardly pointed set screw means forming a bearing for the associated leg and threaded into the lower end of said connecting bore for adjusting the tension of said coil spring, and a plurality of laterally oppositely projecting fingers extending from said cross-bar in the longitudinal transverse plane thereof throughout its length and extending from said tubular sections of said legs in the longitudinal transverse planes thereof pro-viding parallel supports extending transversely of the direction of said cables about which said cables may be woven to restrain the cables within the projected transverse planes of said cross-bar and legs.

References Cited in the file of this patent UNITED STATES PATENTS 1,875,977 Beckwith Sept. 6, 1932 2,274,895 Haniquet Mar. 3, 1942 2,686,649 DeVigier Aug. 17, 1954 FOREIGN PATENTS 53,096 Switzerland June 23, 1911 465,880 Canada June 13, 1950 

